Michael Schumacher has claimed he may not want to continue in Formula 1 beyond the end of his current Mercedes deal, which expires at the end of 2012.
His team-mate Nico Rosberg has signed a new contract to extend his own two-year stay with the German constructor.
"I need a little bit more time to see," said Schumacher ahead of Sunday's Abu Dhabi Grand Prix.
"It is sort of about myself and how we are heading and also some input to see if that is what I want or not."
German newspaper Sport Bild had reported that the seven-time world champion had agreed a one-year extension to continue at Mercedes until the end of 2013.
But Schumacher, who returned to the grid for the 2010 season after giving up his seat at Ferrari at the end of 2006, insists that he has not decided to continue beyond the end of next season.
"According to some journalists, I have. The reality is no, because I told you already several times that this is not the time to talk about it," he added.
"Most important is do I feel it? Do I want it or not? That is something we will find out in the future. Not right now."
Schumacher approved of Mercedes' decision to extend Rosberg's deal, describing the extension as "most logical".
Rosberg switched to Mercedes at the end of the 2009 season from Williams.
The 26-year-old has failed to secure a podium finish this year, but is confident he can win races in a 'Silver Arrow'.
He said: "I have every confidence the team will provide me with a winning car. I am very excited to have extended my contract."
Mercedes came fourth in last year's constructors' championship and are set to finish in the same position again this season.
They have not won a grand prix since taking over Brawn GP in 2009.
But Rosberg, currently ranked seventh in the drivers' world championship, maintains the team will be more competitive in the future.
He added: "To win in a Silver Arrow (the nickname of Mercedes' cars) will be one of the highlights of my life so far and I greatly enjoy helping to lead our team in our quest to become the best in Formula One.
"I am confident we will be able to contribute to the fantastic racing heritage of the Silver Arrows."
Team principal Ross Brawn believes Rosberg is capable of winning the the drivers' championship in the future.
He claims Rosberg has over-achieved, given the limitations of the current Mercedes car.
Brawn said: "Nico is a driver who can win races and championships.
"He has performed exceptionally well for our Silver Arrows team over the past two seasons, achieving results at the very limit of the technical capabilities of our current car.
"As we continue to strengthen our team for the future, we look forward to providing Nico with a car which will enable him to compete right at the front of the field and achieve his deserved first win in Formula 1."